Bethesda announced a series of celebrations on the 25th anniversary of the "radiation" series.

CTOnews.com, October 3 (Xinhua)-- developer Bethesda announced several celebrations in October and released a poster as the game "radiation" celebrates its 25th anniversary this month.

First, Bethesda will launch a week-long free trial for radiation 76, which will begin this week and end on October 10.

Second, Bethesda will offer "a big discount for the entire radiation line", with anniversary sales running through October 12 on Xbox and PlayStation consoles and through October 18 on Steam.

Finally, Bethesda will release an update to radiation Sanctuary next week, adding new content to the free game for the first time in more than four years.

CTOnews.com learned that the radiation series made its debut in 1997 and that radiation 4 in 2015 was one of its best-selling works, selling 1200 million copies worldwide on its release day alone.

The latest work in the series is radiation 76, an online multiplayer game in 2018. Its latest update, released in September, introduces repeatable story-based quests for teams of up to four players to play in Pittsburgh.

As for the next installment of the radiation series, Todd Howard, director of Bethesda Game Studios, recently reiterated that the development of radiation 5 is behind Starry Scroll and Ancient Scroll 6, so it will be years away.